Sapphires related to alkali basalts from the Cerova Highlands, Western Carpathians (southern Slovakia): composition and origin

Rok, strany: 2012, 71 - 82

Blue, grey-pink and pink sapphires from the Cerova Highlands, Western Carpathians (southern Slovakia) have been studied using CL, LA-ICP-MS, EMPA, and oxygen isotope methods. The sapphire occurs as (1) clastic heavy mineral in the secondary sandy filling of a Pliocene alkali basaltic maar at Hajnacka, and (2) crystals in a pyroxene-bearing syenite/anorthoclasite xenolith of Pleistocene alkali basalt near Gortva. Critical evaluation of compositional diagrams (Fe, Ti, Cr, Ga, Mg contents, Fe/Ti, Cr/Ga, Ga/Mg ratios) suggests a magmatic origin for clastic blue sapphires with lower Cr and Mg, but higher Fe and Ti concentrations in comparison to the grey-pink and pink varietes, as well as similar compositional trends with blue sapphire from the Gortva magmatic xenolith. Moreover, blue sapphires show similar δ¹⁸O values: 5.1 ‰ in the Gortva xenolith, 3.8 and 5.85 ‰ in the Hajnacka placer, closely comparable to mantle to lower crustal magmatic rocks. On the contrary, pink and grey-pink sapphires show higher Cr and Mg, but lower Fe and Ti contents and their composition points to a metamorphic (metasomatic) origin.

ISO 690:

Uher, P., Giuliani, G., Szakall, S., Fallick, A., Strunga, V., Vaculovic, T., Ozdin, D., Greganova, M. 2012. Sapphires related to alkali basalts from the Cerova Highlands, Western Carpathians (southern Slovakia): composition and origin. In Geologica Carpathica, vol. 63, no.1, pp. 71-82. 1335-0552. DOI: https://doi.org/10.2478/v10096-012-0005-7

APA:

Uher, P., Giuliani, G., Szakall, S., Fallick, A., Strunga, V., Vaculovic, T., Ozdin, D., Greganova, M. (2012). Sapphires related to alkali basalts from the Cerova Highlands, Western Carpathians (southern Slovakia): composition and origin. Geologica Carpathica, 63(1), 71-82. 1335-0552. DOI: https://doi.org/10.2478/v10096-012-0005-7